Mr Al-Kazhraji, 68, who lives in Wakefield, said: “We came in as usual at eight o’clock and we saw the gate had been opened by force.

“We saw the roller shutter was up and then the fork-lift in the yard, which was unusual. We realised the front and back gate and the main door to the workshop had been broken into.

“It was a sickening feeling, and when I started walking in I was horrified to see how many engines they removed. I was astonished.

“Thirty years of hard work and they come and take that in one.”

Unfortunately, CCTV from a neighbouring business has failed to capture the culprits, but locals claimed to have seen a lorry in the yard that night.

Mr Al-Kazhraji is offering the sum to anyone with information which leads to the engines being recovered and prosecution of those involved.

“The £10,000 reward is serious,” he said. “All my employees have families. It’s a big blow, it will take us a long time to recover.

“We are a family firm, we’ve employed local people for the last 30 years and we’ve suffered badly with this burglary.

“We plead with the public to help with any information. Time is of the essence.”

Det Insp Stef Wiseman, of Kirklees CID, said: “We don’t believe this was a random burglary. The engines are worth a lot of money and we believe the establishment was targeted because of what was in the premises.

“I would appeal to anyone who witnessed any suspicious activity in the area on that night to get in contact. I would also appeal to anyone with an interest in boats to be on the look out too.

“If you are offered a boat engine or engines for sale in a deal that sounds too good to be true, then it probably is.”

The engines include those that are Yamaha, Volvo, Caterpillar, Iveco and Perkins designs, and are in various bright colours as well as in grey.

Call CID on 101. Mr Al-Kazhraji can be contacted on the West End Marine’s number, 01924 478060.